CER - Certified Endoscope Reprocessor Endoscope Sterilization Methods Questions and Answers

Question 1

A reprocessing facility is validating its Ethylene Oxide (EtO) sterilization cycle for flexible endoscopes.
Which of the following sets of parameters are all essential for achieving effective EtO sterilization?

Accepted Answer

Gas concentration, temperature, relative humidity, and exposure time

Answer

Gas concentration, temperature, pressure, and aeration time

Answer

Pre-vacuum depth, gas concentration, exposure time, and post-cycle purge

Answer

Temperature, relative humidity, cycle duration, and biological indicator placement

Question 2

A facility is considering a low-temperature sterilization method for its new heat-sensitive flexible duodenoscopes. They need a method that uses a vapor, is converted to a plasma state to enhance microbial kill, and breaks down into non-toxic byproducts like oxygen and water. Which sterilization method fits this description?

Accepted Answer

Vaporized Hydrogen Peroxide Gas Plasma

Answer

Peracetic Acid Immersion

Answer

Ethylene Oxide (EtO)

Answer

Ozone Sterilization

Question 3

According to ANSI/AAMI ST91, what is the recommended practice for endoscopes that have been processed using a liquid chemical sterilization (LCS) system but are not intended for immediate use?

Accepted Answer

They can be stored in the same manner as endoscopes that have undergone high-level disinfection.

Answer

They can be stored with a claim of being sterile for up to 7 days.

Answer

They must be dried with 70% isopropyl alcohol and then packaged in a sterile container.

Answer

They should be used immediately, as storage is not recommended for liquid chemically sterilized items.

Question 4

A reprocessing technician is using an Automated Endoscope Reprocessor (AER) that utilizes a peracetic acid-based system for liquid chemical sterilization. What is the primary mechanism by which peracetic acid inactivates microorganisms?

Accepted Answer

Oxidation of cell components

Answer

Alkylation of proteins and nucleic acids

Answer

Coagulation of cellular proteins

Answer

Disruption of the cell membrane via a pH change

Question 5

Which of the following statements correctly distinguishes sterilization from high-level disinfection (HLD) in the context of endoscope reprocessing?

Accepted Answer

Sterilization provides a sterility assurance level (SAL) by eliminating all viable microorganisms, including large numbers of bacterial spores.

Answer

Sterilization kills all microorganisms including viruses, while HLD only kills bacteria and fungi.

Answer

HLD is the required minimum for critical endoscopes, while sterilization is optional.

Answer

HLD uses heat and pressure, whereas sterilization exclusively uses low-temperature chemical methods.

Question 6

A hospital's infection control committee is reviewing its endoscope reprocessing protocols. They note that while their AERs perform an excellent high-level disinfection cycle, the final forced-air drying phase is often incomplete, leaving visible moisture in the channels. This significantly increases the risk of:

Accepted Answer

Recontamination and proliferation of waterborne microorganisms.

Answer

Corrosion of the endoscope's internal components.

Answer

Ineffectiveness of the subsequent leak test.

Answer

Fixation of proteins if the manual cleaning was inadequate.